Patient-safe electromechanical switching for pacing with a catheter having multiple electrodes

Abstract

A pacing system includes a signal generator and an electromechanical switch. The signal generator is configured to generate a pacing signal. The electromechanical switch has a plurality of outputs that are configured to be coupled to a plurality of electrodes inserted into a heart of a patient, each output configured to deliver the pacing signal to a respective electrode. The electromechanical switch is configured to route the pacing signal to no more than a single selected one of the outputs at any given time, so as to pace the heart using no more than a single selected one of the electrodes.

The invention claimed is: 
     
       1. A pacing system, comprising:
 a signal generator configured to generate a pacing signal; and 
 an electromechanical switch having:
 a substrate patterned with a plurality of contacts arranged in a circular array, wherein each contact in the circular array is configured to be in electrical communication with an electrode of a plurality of electrodes inserted into a heart of a patient, each contact of the plurality of contacts being configured to deliver the pacing signal to a respective electrode of the plurality of electrodes; and 
 a moving switch attached to a circular rail and configured to move along the circular rail in a circular trajectory over the plurality of contacts and to establish electrical contact with one contact only at any given time, 
 
 wherein the electromechanical switch is configured to route the pacing signal to no more than a single selected one of the contacts at any given time, so as to pace the heart using no more than a single selected one of the electrodes. 
 
     
     
       2. The pacing system according to  claim 1 , wherein the electromechanical switch further comprises:
 a motor, which is configured to move the moving switch. 
 
     
     
       3. The pacing system according to  claim 1 , wherein the substrate of the electromechanical switch is made of a printed circuit board (PCB). 
     
     
       4. The pacing system according to  claim 2 , wherein the motor of the electromechanical switch comprises a stepper motor. 
     
     
       5. The pacing system according to  claim 2 , wherein the moving switch comprises a wheel that is configured to roll over the array of contacts. 
     
     
       6. The pacing system according to  claim 5 , and comprising a processor, which is configured to apply a control loop that adaptively controls the motor to fine-tune a position of the moving switch, to optimize the electrical contact between the wheel and the contact. 
     
     
       7. The pacing system according to  claim 6 , wherein the processor is configured to control the motor based on an electrocardiogram (ECG) sensed via the electrode associated with the contact. 
     
     
       8. The pacing system according to  claim 5 , wherein the wheel is made of metal. 
     
     
       9. The pacing system according to  claim 5 , wherein the wheel is made of an electrically conductive polymer. 
     
     
       10. The pacing system according to  claim 5 , wherein the wheel is made of polymer and is disposed with electrically conducting strips. 
     
     
       11. The pacing system according to  claim 1 , wherein the plurality of contacts comprises multiple reed switches, wherein each reed switch is coupled to a respective contact of the plurality of contacts,
 wherein the moving switch comprises a magnet, which is configured to move over the reed switches and to cause only one reed switch to establish electrical contact at any given time, and 
 wherein the pacing system further comprises a motor configured to move the moving switch. 
 
     
     
       12. The pacing system according to  claim 1 , and comprising a processor, which is configured to command the pacing generator to generate the pacing signal and command the electromechanical switch to route the pacing signal according to a prespecified pacing protocol. 
     
     
       13. The pacing system according to  claim 1 , wherein the pacing signal is unipolar. 
     
     
       14. The pacing system according to  claim 1 , wherein the pacing signal is bipolar, and wherein the pacing system comprises an additional electromechanical switch to form a dual electromechanical switch together with the electromechanical switch, wherein the dual electromechanical switch is configured to route the bipolar pacing signal to no more than a selected pair of the contacts at any given time, so as to pace the heart bipolarly using no more than a selected pair of the electrodes. 
     
     
       15. The pacing system according to  claim 14 , wherein the substrate is a substrate patterned with (1) multiple contacts arranged in a first circular array, wherein each contact in the first circular array is configured to be in electrical communication with a respective electrode of the plurality of electrodes, and (2) multiple contacts arranged in a second circular array, and wherein each contact in the second circular array is configured to be in electrical communication with a respective electrode of the plurality of electrodes,
 wherein the moving switch is a first moving switch attached to a first circular rail and configured to move along the first circular rail over the first circular array of contacts and to establish electrical contact with one contact only of the first circular array at any given time, 
 wherein the dual electromechanical switch further comprises:
 a second moving switch attached to a second circular rail and configured to move along the second circular rail over the second circular array of contacts and to separately establish electrical contact with one contact only of the second circular array at any given time; and 
 a first motor configured to move the first moving switch independent of the second moving switch; and 
 a second motor configured to move the second moving switch independent of the first moving switch. 
 
 
     
     
       16. The pacing system according to  claim 15 , wherein the first array of contacts and the second array of contacts of the dual electromechanical switch are spatially separated in space. 
     
     
       17. The pacing system according to  claim 15 , wherein the first array and the second array of contacts are concentric circular arrays. 
     
     
       18. The pacing system according to  claim 15 , wherein the first array and the second array of contacts are vertically overlaid over one another. 
     
     
       19. The pacing system according to  claim 14 , wherein the substrate is a substrate patterned with (1) multiple reed switches arranged in a first circular array, wherein each reed switch in the first circular array is coupled to a respective output of the plurality of outputs, and (2) multiple reed switches arranged in a second circular array, and wherein each reed switch in the second circular array is coupled to a respective contact of the plurality of contacts,
 wherein the moving switch comprises a first moving switch comprising a magnet, which is configured to move over the first circular array of reed switches and to cause only one reed switch of the first circular array to establish electrical contact at any given time, 
 wherein the pacing system further comprises:
 a second moving switch comprising a magnet, which is configured to move over the second circular array of reed switches and to separately cause only one reed switch of the second circular array to establish electrical contact at any given time; and 
 a first motor configured to move the first moving switch independent of the second moving switch; and 
 a second motor configured to move the second moving switch of the first moving switch. 
 
 
     
     
       20. A method for pacing a heart, the method comprising:
 generating a pacing signal; and 
 using an electromechanical switch having:
 a substrate patterned with a plurality of contacts arranged in a circular array, wherein each contact in the circular array is coupled to a plurality of electrodes inserted into the heart; and 
 a moving switch attached to a circular rail and configured to move along the circular rail in a circular trajectory over the plurality of contacts and to establish electrical contact with one contact only at any given time, 
 
 wherein each contact is configured to deliver the pacing signal to a respective electrode so as to pace the heart using no more than a single selected one of the electrodes. 
 
     
     
       21. A manufacturing method, comprising:
 patterning a substrate with multiple contacts arranged in a circular array; 
 providing a moving switch attached to a circular rail, which is configured to move along the circular rail in a circular trajectory over the circular array and to establish electrical contact with one contact only at any given time; and 
 providing one or more motors, which are configured to move the moving switch. 
 
     
     
       22. A manufacturing method, comprising:
 patterning a substrate with multiple contacts arranged in a first circular array, and multiple contacts arranged in a second circular array; 
 providing a first moving switch mechanically coupled to a first circular rail, which is configured to move over the first circular array and to establish electrical contact with one contact only of the first circular array at any given time; 
 providing a second moving switch mechanically coupled to a second circular rail, which is configured to move over the second circular array and to separately establish electrical contact with one contact only of the second circular array at any given time; and 
 coupling a first motor to the first moving switch, the first motor configured to move the first moving switch independent of the second moving switch; and 
 coupling a second motor to the second moving switch, the second motor configured to move the second moving switch independent of the first moving switch.